Pull-through registries

A pull-through registry is a proxy that sits between your local Docker installation and a remote Docker registry. It caches the images you pull from the remote registry, and if another user on the same network tries to pull the same image, the pull-through registry will serve it to them directly, rather than pulling it again from the remote registry. The Container Runtime Interface (CRI) in this lab is set up to use local pull-through registries for the remote registries docker.io, quay.io and ghcr.io on each cluster.

List all images in a registry:

curl -s 127.0.0.1:5011/v2/_catalog | jq # docker.io
curl -s 127.0.0.1:5012/v2/_catalog | jq # quay.io
curl -s 127.0.0.1:5013/v2/_catalog | jq # ghcr.io

List tags for a given image:

curl -s 127.0.0.1:5012/v2/argoproj/argocd/tags/list | jq

Get the manifest for a given image and tag:

curl -s http://127.0.0.1:5012/v2/argoproj/argocd/manifests/v2.4.7 | jq